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25kv URD cable in tray

25kv URD cable in tray

25kv URD cable in tray

(OP)
Is it ok to install 25kv URD cable in ladder tray

RE: 25kv URD cable in tray

In what country and what application?  It probably would not comply with NEC in the US unless the cable was UL listed as MV cable for use in tray, which seems unlikely.  

If you're a US utility, you can do whatever you want, without regard to NEC in substations and power plants.

Tray cable is tested for flame propagation and URD probably is not.  

For NEC compliance it would also have to be isolated from any low voltage cable by a metal barrier.  

RE: 25kv URD cable in tray

Why Underground residential Distribution (URD) is proposed to be installed in cable tray?
Is the cable sunlight (UV) resistance rated?
Even if the cable tray system meet code requirement, URD cable installed in tray may not be the most economical choice since the concentric neutral can be saved if the metallic cable trays is permitted to be used as Equipment grounding conductor (EGC) where continuous maintenance and supervision ensures that qualified persons will service the installed cable tray system as stated in NEC Section 318-3(c).

RE: 25kv URD cable in tray

Cuky2000

Little bit off topic, but:
How do you insert such an image?
Is it a certain type of file, a certain method or just magic?

Thanks


Regards

Ralph

RE: 25kv URD cable in tray

High Ralph,


This is an awesome tool to illustrate our point of view.

For image available in the web, use the [img] tag. The way to show this in the post is typing the following:

[img  “internet address” ]

“Example of internet address” =  http://www.matel.com.mx/gif/cablepic/e07.GIF

For additional details attaching images and other editing tips, access TGML tags list from the preview mode on the post window.

RE: 25kv URD cable in tray

(OP)
DPC
 It is in Canada
Need to carry neutral from main sub station to existing 25kv O/H ploe line. Because bldg is in the way, Cannot run O/H line all the way. So part of run is cable on top of roof.
Since hard to find 25kv 4C plus ground armour cable. Thinking to run URD in tray on top of roof.

Or any other suggestion

RE: 25kv URD cable in tray

JWA1
Who owns the cable?  IF it's a utility and the NEC does not apply.  I have seen try use in large vaults ( approaching swimming pools in size ) to support red stripe cable.

RE: 25kv URD cable in tray

Thanks cuky2000

Maybe I have to replace my glasses...


Regards

Ralph

RE: 25kv URD cable in tray

(OP)
BJC
It is not utility. I will be contractor supplied.
It is industrial plant.
Cannot run underground.

RE: 25kv URD cable in tray

You might consider MC cable - metal-clad with continuous corrugated armor (Okonite C-L-X).  It is made up to 35kV, includes ground wire and the armor sheath can be used as a neutral/ground.  It is listed for tray use and for direct burial.  

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